Fluidization devices and methods of use

ABSTRACT

A device for fluidizing and delivering a powdered agent, including a canister extending longitudinally from a first to a second end and defining a space within which a powdered agent is received, an inlet coupleable to a gas source for supplying gas to the space to fluidize the powdered agent to create a fluidized mixture, an outlet via which the gas mixture is delivered to a target area, a tube extending from the outlet into the interior space, the tube including a slot extending through a wall thereof so that gas mixture is passable from the interior space through the outlet via the second end and the slot, and a door movably coupled to the tube so that the door is movable over the slot to control a size of the slot open to the interior space of the canister.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority from U.S. ProvisionalApplication No. 62/740,242, filed on Oct. 2, 2018, and U.S. ProvisionalApplication No. 62/747,863, filed on Oct. 19, 2018, each of which isincorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to endoscopic medical devicesand methods of use. More particularly, in some embodiments, thedisclosure relates to devices and methods for fluidization of materials,e.g., powders or reagents, for dispensing the materials to a target sitein a patient.

BACKGROUND

Therapeutic agents in the form of dry powders such as, for example,hemostatic agents, may be delivered to a target site within a livingbody using a fluidization and delivery device. Such devices havegenerally included a chamber in which powder is received and introducedto high flow gases to create a fluidized bed. This creates a two-phasemixture containing particulate solids suspended in gas. The suspensionretains the properties of the gaseous fluid and will move in a directionfrom high to low pressure, effectively delivering the particulate to thelower pressure region. Hemostatic powder, for example, can be deliveredto a target location (e.g., a bleeding site) through an endoscopiccatheter using this method. Studies have shown that when a particulatedelivery rate of hemostatic powder to the bleeding location falls belowa threshold level may, in some cases, be no longer effective inachieving initial hemostasis. Current powder fluidization and deliverydevices, however, often show a decrease in powder delivery rate overtime.

SUMMARY OF THE DISCLOSURE

The present embodiments are directed to a device for fluidizing anddelivering a powdered agent, comprising a canister extendinglongitudinally from a first end to a second end and defining an interiorspace within which a powdered agent is received, an inlet coupleable toa gas source for supplying gas to the interior space to fluidize thepowdered agent received therewithin to create a fluidized mixture, anoutlet via which the gas mixture is delivered to a target area fortreatment, a tube extending from a first end in communication with theoutlet to a second end extending into the interior space, the tubeincluding a slot extending through a wall thereof so that gas mixture ispassable from the interior space through the outlet via the second endand the slot, and a door movably coupled to the tube so that the door ismovable over the slot to control a size of the slot open to the interiorspace of the canister.

In an embodiment, the door may be configured as an overtube movablymounted over the tube.

In an embodiment, the device may further comprise a stabilizing ringextending radially outward from the overtube to an interior surface ofthe canister to fix the tube relative to the canister.

In an embodiment, the canister may be rotatable relative to the tube tomove the overtube longitudinally relative to the tube and control thesize of the slot open to the interior space.

In an embodiment, the device may further comprise a lid coupleable tothe canister to enclose the interior space, the inlet and the outletconfigured as openings extending through the lid.

In an embodiment, the device may further comprise a delivery cathetercoupleable to the outlet, the delivery catheter sized and shaped to beinserted through a working channel of an endoscope to the target area.

The present embodiments are also directed to a device for fluidizing anddelivering a powdered agent, comprising a canister extendinglongitudinally from a first end to a second end and including a firstinterior space within which a powdered agent is received, a first inletcoupleable to a gas source for supplying gas to the interior space tofluidize the powdered agent received therewithin to create a fluidizedmixture, an outlet via which the gas mixture is delivered to a targetarea for treatment from the first interior space, and a filler chamberin communication with the first interior space via a filler inlet, thefiller chamber containing a filler material passable from the fillerchamber to the first interior space to maintain a substantially constantvolume of material therein, wherein the material includes at least oneof the powdered agent and the filler material.

In an embodiment, the filler material may include one of mock particles,beads, bounce balls, and a foam material.

In an embodiment, the filler material may be sized, shaped andconfigured so that the filler material cannot be passed through theoutlet.

In an embodiment, the filler chamber may be supplied with a gas to drivethe filler material from the filler chamber into the first interiorspace.

In an embodiment, the filler chamber may be configured as a secondinterior space defined via the canister.

In an embodiment, the second interior space may include an angledsurface directing the filler material to the filler inlet.

In an embodiment, the filler material may be additional powdered agent.

In an embodiment, the device may further comprise a door movablerelative to the filler inlet between a first configuration, in which thedoor covers the filler inlet, to a second position, in which the dooropens the filler inlet to permit filler material to pass therethroughfrom the filler chamber to the first interior space via gravity.

In an embodiment, the device may further comprise a turbine connected toa paddle housed within the filler inlet, the turbine driven by a flow ofgas so that, when a flow of gas is received within a flow path housingthe turbine, the turbine rotates to correspondingly rotate the paddle sothat filler material within the filler chamber is actively driventherefrom and into the first interior space.

The present embodiments are also directed to a method, comprisingsupplying a gas to an interior space within a canister within which apowdered agent is received to fluidize the powdered agent, forming afluidized mixture and delivering the fluidized mixture to a target areawithin a patient body via a delivery catheter inserted through a workingchannel of an endoscope to the target area, wherein during delivery ofthe fluidized mixture, a door movably mounted over the tube is movedrelative to a slot extending through a wall of a tube extending into theinterior space of the canister in communication with the deliverycatheter, to control a size or a portion of the slot exposed to theinterior space.

The present embodiments are also directed to a device for fluidizing anddelivering a powdered agent, comprising a canister extendinglongitudinally from a first end to a second end and defining an interiorspace within which a powdered agent is received, an inlet coupleable toa gas source for supplying gas to the interior space to fluidize thepowdered agent received therewithin to create a fluidized mixture, anoutlet via which the gas mixture is delivered to a target area fortreatment, and a piston movably coupled to the canister, the pistonmovable from an initial configuration, in which the piston is coupled tothe first end of the canister, toward the second end of the canister toreduce a volume of the interior space as a volume of the powdered agentis reduced during delivery of the fluidized mixture to the target area.

In an embodiment, each of the inlet and the outlet may extend through aportion of the piston.

In an embodiment, the outlet may be coupleable to a delivery cathetersized and shaped to be inserted through a working channel of anendoscope to the target area.

In an embodiment, the piston may be movable via one of a pneumaticcylinder and motor.

In an embodiment, the device may further comprise a chamber connected tothe first end on the canister on a side of the piston opposing theinterior space of the canister, the chamber housing an expandable memberwhich is configured to receive gas during delivery of the fluidizedmixture so that the expandable mixture expands to move the piston towardthe second end of the canister.

In an embodiment, the expandable member may be configured to beconnected to the gas source via a connecting member including a one wayvalve which permits a flow of gas into the expandable member whilepreventing a flow of gas out of the expandable member.

In an embodiment, the device may further comprise a bypass connected tothe first end of the canister and coupled to the piston via a threadedrod, the bypass housing a turbine connected to the threaded rod andbeing configured to receive a flow of gas therethrough so that, when gasflows through the bypass during delivery of the fluidized mixture, theturbine and threaded rod rotate to move the piston toward the second endof the canister.

The present embodiments are directed to a device for fluidizing anddelivering a powdered agent, comprising a canister extendinglongitudinally from a first end to a second end and including a firstinterior space within which a powdered agent is received, an inletcoupleable to a gas source for supplying gas to the interior space tofluidize the powdered agent received therewithin to create a fluidizedmixture, an outlet via which the gas mixture is delivered to a targetarea for treatment, and an expandable member movable between an initialbiased configuration and an expanded configuration in which theexpandable member is deformed so that a portion of the expandable memberextends into the first interior space to reduce a volume thereof as avolume of the powdered agent therein is reduced during delivery of thefluidized mixture to the target area.

In an embodiment, the canister may further include a second interiorspace configured to receive a gas therein during delivery of thefluidized mixture to the target area.

In an embodiment, the first and second interior spaces may be separatedfrom one another via an expandable member, a pressure differentialbetween the first and second interior spaces causing the expandablemember to deform into the first interior space.

In an embodiment, the expandable member may be a diaphragm.

In an embodiment, the first interior space may be defined via aninterior wall of the expandable member and the second interior space maybe defined via an exterior wall of the expandable member and an interiorsurface of the canister.

In an embodiment, the expandable member may be substantiallycylindrically shaped.

In an embodiment, the expandable member may extend from the first end ofthe canister to the second end of the canister.

In an embodiment, the expandable member may be a balloon housed withinthe canister and configured to receive a gas therewithin so that, as theballoon is inflated, the balloon fills the first interior space.

The present embodiments are also directed to a method, comprisingsupplying a gas to an interior space within a canister within which apowdered agent is received to fluidize the powdered agent, forming afluidized mixture, and delivering the fluidized mixture to a target areawithin a patient body via a delivery catheter inserted through a workingchannel of an endoscope to the target area, wherein during delivery ofthe fluidized mixture, a volume of the interior space of the canister isreduced to correspond to a reduction in volume of the powdered agent sothat a rate of delivery of the fluidized mixture remains substantiallyconstant.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate various embodiments and togetherwith the description, serve to explain the principles of the disclosedembodiments.

FIG. 1 shows a schematic view of a device according to a firstembodiment, in a first configuration;

FIG. 2 shows a perspective view of the device of FIG. 1, in a secondconfiguration;

FIG. 3 shows a schematic view of a device according to anotherembodiment of the present disclosure;

FIG. 4 shows a schematic view of a device according to an alternateembodiment of the present disclosure;

FIG. 5 shows a schematic view of a device according to yet anotherembodiment of the present disclosure;

FIG. 6 shows a lateral cross-sectional view of the device of FIG. 5along the line 6-6;

FIG. 7 shows a schematic view of a device according to anotherembodiment of the present disclosure;

FIG. 8 shows a schematic view of a device according to yet anotherembodiment of the present disclosure, in a first configuration;

FIG. 9 shows a schematic view of the device of FIG. 8, in a secondconfiguration;

FIG. 10 shows a schematic view of a device according to an alternateembodiment of the present disclosure, in a first configuration;

FIG. 11 shows a schematic view of the device of FIG. 10, in a secondconfiguration;

FIG. 12 shows a schematic view of a device according to an embodiment ofthe present disclosure;

FIG. 13 shows a schematic view of a device according to an alternateembodiment of the present disclosure;

FIG. 14 shows a schematic view of a device according to anotheralternate embodiment of the present disclosure;

FIG. 15 shows a bottom view of the device according to FIG. 14;

FIG. 16 shows a schematic view of a device according to anotherembodiment of the present disclosure;

FIG. 17 shows a schematic view of a device according to yet anotherembodiment of the present disclosure;

FIG. 18 shows a schematic view of a device according to anotherembodiment;

FIG. 19 shows a schematic view of device according to yet anotherembodiment of the present disclosure; and

FIG. 20 shows a schematic view of a device according to an alternate ofthe present disclosure.

DETAILED DESCRIPTION

Both the foregoing general description and the following detaileddescription are exemplary and explanatory only and are not restrictiveof the features, as claimed. As used herein, the terms “comprises,”“comprising,” “having,” “including,” or other variations thereof, areintended to cover a non-exclusive inclusion such that a process, method,article, or apparatus that comprises a list of elements does not includeonly those elements, but may include other elements not expressly listedor inherent to such a process, method, article, or apparatus. In thisdisclosure, relative terms, such as, for example, “about,”“substantially,” “generally,” and “approximately” are used to indicate apossible variation of ±10% in a stated value or characteristic.

The present disclosure may be further understood with reference to thefollowing description and the appended drawings, wherein like elementsare referred to with the same reference numerals. The present disclosurerelates to devices and methods for delivering fluidized powder at aconstant delivery rate to increase a duration of a period during whichan effective rate of delivery of the powdered agent may be maintainedallowing a user (e.g., a physician) to treat more bleeding areas withouthaving the delivery rate of the powder fall below the threshold raterequired to achieve hemostasis. This can reduce the number of devicesneeded per procedure (and/or the number of times a device needs to bereloaded or reset) thereby reducing treatment time. In one embodiment, adevice includes features for changing a size of a powder exit openingduring delivery of the fluidized powder to maintain a desired rate ofdelivery over time. In another embodiment, a device includes aturbulator plate to prevent settling of powder within a canister tomaintain a desired rate of delivery of the powder. In anotherembodiment, a device includes a plurality of powder exit slotsdistributed about a tube extending into a canister in which the powderis received to prevent uneven powder distribution within the canister.In yet another embodiment, a device maintains a constant volume ofmaterial within the canister to maintain a substantially constantdelivery rate by injecting filler material and/or additional powder asfluidized powder is delivered. In another embodiment, a user (e.g.,physician) to maintain an effective and optimal delivery zone for alonger duration of time. This would allow the user to treat morebleeding areas, reducing the number of devices needed per procedure andthereby reducing treatment time. Embodiments describe a powderfluidization chamber and delivery device which, over time, reduces aninterior volume of a fluidizing canister as the powder volume isdecreased during delivery. The canister volume may be reduced tomaintain a powder to canister volume ratio throughout the entireprocedure to maintain a constant delivery rate during the treatment. Itwill be understood by those of skill in the art that all of thesefeatures maintain a desired fluidized powder delivery rate during thecourse of treatment. For example, the desired rate of delivery may bemaintained substantially constant during a period of application of thepowder or the rate may fluctuate within a desired range of deliveryrates without falling below a critical threshold delivery rate (e.g., arate below which delivery of the powder is no longer effective for itsintended therapeutic purpose).

As shown in FIGS. 1 and 2, a device 100 for fluidizing and delivering apowdered agent (e.g., a powdered therapeutic agent) to a site within aliving body (e.g., a target site) according to an embodiment of thepresent disclosure comprises a canister 102 configured to receive thepowdered agent (e.g., hemostatic agent) within an interior space 104thereof. Hemostatic agents may include, for example, powdered agentsusing granular chitosan salt, Zeolite powder, smectite clay and PolyAcrylic Acid, or polysaccharide hemospheres derived from potato starch.The device 100 includes an inlet 106 via which gas (e.g., CO₂) issupplied to the canister 102 to fluidize the powdered agent and form afluidized powder mixture and an outlet 108 via which the fluidizedpowder mixture exits the canister 102 to be delivered to the target site(e.g., bleeding site) via, for example a flexible delivery device (e.g.,an endoscope) inserted through a body lumen accessed via a natural bodyorifice. A tube 110 (e.g., a hypotube) extends from the outlet 108 andinto the interior space 104 of the canister 102 so that the fluidizedpowder mixture may be received therein to exit the canister 102. Thetube 110 in this embodiment includes a slot 112 extending through a wallthereof so that fluidized powder mixture may exit the canister 102 fromboth an end 114 of the tube 110 and through the slot 112. The device 100according to this embodiment further comprises an overtube 116 movablymounted over a portion of the tube 110 so that the overtube 116 may bemoved along a length of the tube 110 to extend over the slot 112,controlling a size of an opening of the slot 112. Testing has shown thatincreasing the slot size increases the powder delivery rate whiledecreasing the slot size decreases the powder delivery rate. Theovertube 116 is movable relative to the tube 110 from an initialconfiguration, in which the overtube 116 at least partially covers theslot 112 toward an open configuration, in which the overtube 116 ismoved along a length of the tube 110 to gradually increase the size ofthe slot 112 during the course of the treatment procedure so that therate of delivery of the fluidized powder delivery may be maintainedabove a threshold level (e.g., be held substantially consistent overtime) even as a volume of the powdered agent within the canister 102decreases as the powder is dispensed. It will be understood that afluidized powder/material includes, but is not limited to, apowder/material that acquires the characteristics of a fluid by passinga propellant fluid (such as a gas) with in or through it, and also anagitized powder/material which is a material that follows a propellantfluid or is pushed by a propellant fluid.

According to an embodiment, a target delivery rate may be, for example,greater than 1 gram for every 5 seconds of delivery. The device 100 mayprovide the best delivery results when the canister 102 is approximately45% to 80% filled with the powdered agent. For example, at 80% fill thetarget rate may be sustained for 30 delivery seconds. This delivery rateis also dictated by the amount of gas that the device 100 may use fordelivery. By gradually increasing the size of the slot 112 through whichthe fluidized powder mixture may exit the canister 102, the deliveryrate may be maintained (e.g., past 30 delivery seconds) even as thevolume of the powdered agent within the canister 102 decreases.

The canister 102 in this embodiment extends longitudinally from an openfirst end 118 to a closed second end 120 to define the interior space104, which is configured to receive the powdered agent therein. A lid122 is coupled to the first end 118 to enclose the interior space 104and prevent the powdered agent and/or gas from leaking from the interiorspace 104. In one embodiment, the lid 122 is received within the firstend 118 and coupled thereto. The inlet 106 and/or the outlet 108 in thisembodiment are configured as openings extending through the lid 122. Itwill be understood by those of skill in the art, however, that the inlet106 and the outlet 108 may have any of a variety of configurations solong as the inlet 106 and the outlet 108 are connectable to a gas sourceand a delivery member, respectively, for supplying a high flow gas tothe powdered agent to fluidize the powdered agent and deliver thefluidized powder mixture to the target site. For example, the inlet 106may be coupled to a connecting member 124 which connects the gas sourceto the inlet 106. In an embodiment, gas may be supplied to the canister102 at a pressure ranging from between 5 and 20 psi and/or a flow rateof 8-15 standard liters per minute. The outlet 108 in this embodiment iscoupled to a flexible delivery catheter 126 sized, shaped and configuredto be inserted through a working channel of a flexible endoscope to thetarget site within a living body. In one example, the delivery catheter126 may have an inner diameter between 0.065 inches and 0.11 inches. Inanother embodiment, the inlet 106 and the outlet 108 may extend througha portion of the canister 102.

The tube 110 extends from a first end 128 connected to the outlet 108 toa second end 114 extending into the interior space 104. As describedabove, the tube 110 in FIGS. 1 and 2 also includes slot 112, whichextends through the wall of the tube 110. The slot 112 in thisembodiment is positioned proximate the first end 128 so that thefluidized powder mixture may exit the interior space 104 of the canister102 via one of second end 114 of the tube 110 and the slot 112 proximatethe first end 128.

The overtube 116 is movably mounted over a portion of a length of thetube 110. The overtube 116 is movable relative to the tube 110 so that,as the overtube 116 moves over the tube 110, an area of the slot 112covered by the overtube 116 is varied to control a size of a portion ofthe slot 112 exposed to the interior space 104 and through which thefluidized powder mixture may exit the interior space 104 of the canister102. For example, in an initial configuration, the overtube 116 extendsover the entire slot 112 so that the slot 112 is completely covered,preventing any fluidized powder mixture from exiting therethrough.During the course of treatment of the target site, however, the overtube116 may be moved relative to the tube 110 to increase the size of theportion of the slot 112 exposed and through which the fluidized powdermay exit to maintain the delivery rate of the fluidized powder mixtureat a desired level (e.g., above a threshold delivery rate). For example,FIG. 2 shows the slot 112 when it is partially covered via a portion ofthe overtube 116 and FIG. 3 shows the slot 112 when it is entirelyexposed. Although the embodiment describes an initial configuration inwhich the entire slot 112 is covered, it will be understood by those ofskill in the art that, in an initial configuration, the overtube 116 mayhave any of a variety of positions relative to the slot 112, so long asthe size of the slot 112, through which the fluidized powder may exit,is increased during the course of treatment as the powder in thecanister 102 is dispensed.

It will also be understood by those of skill in the art that theovertube 116 may be moved relative to the tube 110 via any of a varietyof mechanisms. In one embodiment, the overtube 116 may be connected to astabilizing ring 130 which extends, for example, radially outward fromthe overtube 116 to an interior surface of the canister 102 to fix aposition of the overtube 116 relative to the canister 102. The canister102 and the tube 110 in this example are rotatably coupled to oneanother so that, when the canister 102 is rotated relative to the tube110, the overtube 116 correspondingly rotates about the tube 110 whilealso moving longitudinally relative to the tube 110 to increase (ordecrease, depending on the direction of rotation) a size of the slot 112through which the fluidized powder mixture may exit. In one example, thelid 122, from which the tube 110 extends, includes cam paths 123extending along a partially helical path, within which an engagingfeature (e.g., a protrusion) of the canister 102 rides so that, as thecanister 102 and, consequently, the overtube 116 are rotated relative tothe lid 122 and the tube 110, the overtube 116 moves longitudinallyrelative to the tube 110. As would be understood by those skilled in theart, the cam paths 123 and the corresponding engaging features of thecanister 102 function similarly to a threaded engagement between thecanister 102 and the lid 122 to achieve the desired relative movementbetween the overtube 116 and the tube 110.

Although the embodiment describes the size of the portion of the slot112 available for fluidized powder mixture to exit as controlled via theovertube 116, the size of the slot 112 may be controlled via any “door”having any of a variety of structures and geometries so long as the“door” may be gradually opened during the course of a treatmentprocedure to maintain a desired flow rate of therapeutic agent out ofthe canister 102. Movement of the overtube 116 or any other “door” maybe actuated mechanically, e.g., by physically twisting the overtube 116,or may be actuated pneumatically by the flow of gas. In addition,although the embodiment shows and describes a single slot 112, the tube110 may include more than one slot 112, which may be covered and/orexposed, as desired, via any of a number of door mechanisms, asdescribed above.

According to an example method using the device 100, the canister 102 isfilled with a powdered agent such as, for example, a hemostatic agent,prior to assembly of the device 100. Upon filling the canister 102 witha desired amount of powdered therapeutic agent, the canister 102 isassembled with the lid 122 to seal the powdered agent therein. The inlet106 is then coupled to the gas source via, for example, the connectingmember 124 and the outlet 108 is coupled to the delivery catheter 126.The delivery catheter 126 is then inserted to the target site within theliving body (e.g., through a working channel of a delivery device suchas, for example, an endoscope). High flow gas is introduced into theinterior space 104 of the canister 102 to form the fluidized powdermixture. The user may depress a trigger or other controller to spray thefluidized mixture and to deliver the fluidized mixture to the target are(e.g., a bleeding site) to provide treatment thereto. As the fluidizedpowder mixture is being delivered to the target site, the user mayphysically rotate the canister 102 relative to the tube 110 to increasethe size of the slot 112 through which the fluidized mixture is exitingthe interior space 104 to maintain a desired flow level. Alternatively,if a trigger is being used to control delivery of the fluidized powdermixture, when the trigger is depressed, a pneumatic cylinder or motormay be operated to rotate and move the lid 122 relative to the canister102 so that a larger cross-sectional area of the slot 112 is exposed,increasing the size of the slot 112 through which the fluidized mixturemay exit the interior space. Thus, as a volume of the powdered agentwithin the canister 102 is decreased, the cross-sectional area of theslot 112 that is exposed is increased to maintain a substantiallyconstant delivery rate of the fluidized powder mixture. Alternatively,sensors may detect a flow rate and automatically control the opening ofthe slot 112 to ensure that a desired flow rate is maintained.

A device 200 according to another embodiment of the present disclosure,shown in FIG. 3, is substantially similar to the device 100 as describedabove unless otherwise indicated. The device 200 comprises a canister202 defining an interior space 204 within which a powdered agent isreceived. Similarly to the device 100, the interior space 204 isenclosed via a lid 222 coupled thereto so that the powdered agentcontained within the interior space 204 forms a fluidized powder mixturewhen the interior space 204 is supplied with a high flow gas via aninlet 206. The fluidized powder mixture exits the interior space 204 viaan outlet 208 to be delivered to a target site within a patient duringtreatment. To maintain a desired delivery rate as the volume of thepowdered agent in the interior space 204 decreases during the course oftreatment, the lid 222 includes a turbulator plate 230. As gas passesthrough the turbulator plate 230, the turbulator plate 230 vibratesand/or rattles to prevent, or at least reduce, settling of the powderedagent contained within the canister 202. Without the turbulator plate230, during the course of treatment, some powdered agent would otherwisesettle into an equilibrium state, resisting fluidization and making itdifficult to maintain a desired delivery rate of the therapeutic agent.

Similarly to the canister 102, the canister 202 extends longitudinallyfrom an open first end 218 to a closed second end 220 to define theinterior space 204. The lid 222 is coupled to the first end 218 toenclose the interior space 204 and contain the powdered agent therein.The inlet 206 and the outlet 208 are configured as openings extendingthrough the lid 222 in communication with the interior space 204.Although not shown, similarly to the device 100, the outlet 208 includesa tube extending therefrom and into the interior space 204 to allow thefluidized powder mixture to exit via the tube and the outlet 208.

The turbulator plate 230 in this embodiment extends along a portion ofthe lid 222 which faces away from the interior space 204. In thisembodiment, the turbulator plate 230 includes an opening 232 extendingthrough a wall 234 thereof, the opening 232 being configured to beconnected to a gas source via, for example, a connecting element 224.The turbulator plate 230 extends along the lid 222 so that the opening232 is in communication with the inlet 206. Thus, gas passes through theturbulator plate 230 and into the interior space 204 via the inlet 206.An interior 236 of the turbulator plate 230 includes a plurality ofstructures 238 such as, for example, ribs, bumps or bosses, which causethe flow of gas therethrough to be turbulent, imparting a vibratoryresponse in the turbulator plate 230. The vibration in turn prevents thepowdered agent from settling on the lid 222. Thus, the flow of gasthrough the turbulator plate 230 and into the interior space 204 causesboth the vibration of the turbulator plate 230 and the fluidization ofthe powered agent within the canister 202. A magnitude of the vibrationmay be controlled via control of the rate at which gas is passed throughthe turbulator plate 230 as would be understood by those skilled in theart. In this embodiment, the magnitude of vibration of the turbulatorplate 230 is held constant over time, for as long as the user isdepressing a trigger to feed gas to the canister 202. The fluidizedpowder agent exits the canister 202 via the outlet 208, which is not incommunication with the interior 236 of the turbulator plate 230. Theoutlet 208 in this embodiment is coupled to a delivery catheter 226 fordelivering the fluidized powder mixture to the target site.

In an alternate embodiment, as shown in FIG. 4, a device 200′ issubstantially similar to the device 200 described above, unlessotherwise indicated. In this embodiment, a turbulator plate 230′ extendsalong a portion of a lid 222′, which encloses an interior space 204′defined via a canister 202′, and includes a first opening 232′ and asecond opening 240′ extending through a wall 234′ thereof. Neither thefirst opening 232′ nor the second opening 240′ are in communication withan inlet 206′ and an outlet 208′ of the device 200′. Each of the inlet206′ and the first opening 232′ are configured to be connected to a gassource for supplying gas to the interior space 204′ and the turbulatorplate 230′, respectively. Each of the inlet 206′ and the first opening232′ is connected to the same or different gas sources.

Gas supplied to the turbulator plate 230′ via the first opening 232′passes through the turbulator plate 230′ and exits the turbulator plate230′ via the second opening 240′. Gas may, for example, be supplied tothe turbulator plate 230′ at a constant rate while the powdered agent isbeing fluidized and delivered to the target site to maintain a constantmagnitude of vibration. Alternatively, the flow of gas supplied to theturbulator plate 230′ may be changed over time, or intermittently, tochange a magnitude of vibration, as desired, to optimize the rate ofdelivery of the fluidized powder mixture. It will be understood by thoseof skill in the art, however, that the function of the turbulator plate230′ remains otherwise the same as the device 200, keeping the powderedagent from settling on the lid 222′.

As shown in FIGS. 5 and 6, a device 300 according to another embodimentof the present disclosure is substantially similar to the devices 100,200, unless otherwise indicated. The device 300 comprises a canister 302defining an interior space 304 within which a powdered agent (e.g.,hemostatic agent) is received and fluidized via a high flow gas fordelivery to a target site (e.g., bleeding site) for treatment. Theinterior space 304 is enclosed via a lid 322 attached to an open end ofthe canister 302 and gas is supplied to the interior space 304 via aninlet 306 extending through the lid 322. The resulting fluidized powdermixture exits the interior space 304 via an outlet 308 extending throughthe lid 322 to be delivered to the target site. The device 300 alsoincludes a tube 310 extending from a first end 328 connected to theoutlet 308 to a second end 314 extending into the interior space 304.Rather than a single slot extending through a wall of the tube 310,however, the tube 310 includes a plurality of slots 312 distributedabout the tube 310 to prevent uneven distribution of powder within thecanister 302 and prevent powder build up on any side of the tube 310,which may decrease fluidized powder mixture delivery rates.

In one embodiment, as shown in FIG. 6, the tube 310 includes four slots312, distributed about the tube 310 and spaced equidistantly from oneanother. The slots 312 in this embodiment are positioned proximate thefirst end 328. It will be understood by those of skill in the art,however, that the number, position and configuration of the slots 312may be varied.

As shown in FIG. 7, a device 400 according to another embodiment of thepresent disclosure is substantially similar to the devices 100, 200, and300 described above, unless otherwise indicated. The device 400comprises a canister 402 defining an interior space 404 within which apowdered agent 405 is received and fluidized to form a fluidized powdermixture for delivery to a target site of within a living body.Similarly, the device 400 may include a lid 422 enclosing the interiorspace 404 along with an inlet 406 via which gas is supplied to theinterior space 404 to fluidize the powdered agent 405 and an outlet 408via which the fluidized powder agent exits the canister 402 to bedelivered to the target site. The device 400 may also include a tube 410extending into the interior space 404 in communication with the outlet408. The device 400 further comprises a filler chamber 450 coupled tothe canister 402, in communication with the interior space 404 of thecanister 402. The filler chamber 450 houses filler material 452 such as,for example, mock particles, beads, tiny “bounce balls” or a foammaterial, which is injected into the canister 402 as fluidized powdermixture exits the canister 402 to make up for a loss in volume of thepowdered agent as the fluidized powder mixture is delivered to thetarget site. The filler material 452 is injected into the canister 402to maintain a constant ratio of volume of material (e.g., powdered agentand filler) to volume of gas within the canister 402 to maintain adesired rate of delivery of the fluidized powder mixture to the targetsite.

The filler chamber 450 may be connected to the canister 402 so that thefiller material 452 passes from the filler chamber 450 to the canister402 via a filler inlet 454. In one embodiment, the filler chamber 450may also include a gas inlet 456 so that, when a user actuates thedelivery of the fluidized powder mixture to the target site via, forexample, pressing a trigger, gas is supplied to both the canister 402and the filler chamber 450. The gas supplied to the filler chamber 450drives the filler material 452 out of the filler chamber 450 into thecanister 402. The filler chamber 450 may include a pressure regulator toregulate the gas inlet pressure, as necessary, to regulate the volume offiller material 452 being supplied to the canister 402 to correspond tothe volume of powdered agent 405 exiting the canister 402. In oneembodiment, the filler inlet 454 may be sized, shaped and/or otherwiseconfigured to facilitate passage of a single stream of filler material452 (e.g., beads) therethrough into the canister 402.

Filler material 452 is configured to be able to enter the interior space404 of the canister 402, but is prevented from exiting the canister 402during delivery of the fluidized powder mixture. In one embodiment, thisis achieved via a sizing of the individual particles of the fillermaterial 452. For example, the filler material 452 may be sized and/orshaped to prevent it from entering the tube 410 and/or the outlet 408.In other words, each bead or particle of the filler material 452 isselected to be larger than an opening of the tube 410 and/or an openingof the outlet 408. The filler material 452 is sized and shaped to belarge enough to prevent the filler material from exiting the canister402, while also being configured to bounce off walls of the canister 402as the powdered agent is moved within the interior space 404 and isfluidized to prevent clogging of the device 400.

Thus, in use, the canister 402 of the device 400 loses powder duringdelivery of the fluidized powder agent, but will compensate for the lossby simultaneously supplying the canister 402 with a corresponding volumeof filler material 452. The rate of delivery of filler material 452 intothe canister 402 may be determined by calculating a powder volume thathas been lost given a fluidized powder mixture delivery rate, andadjusting it based on volume and flow rate differences of the fillermaterial 452 versus the powdered agent 405. The rate of delivery offiller material 452 into the canister 402 is selected to compensate forthe loss in volume of the powder 405 to maintain a substantiallyconstant fluidized powder mixture delivery rate. Although the inlet 406of the canister 402 and the gas inlet 456 of the filler chamber 450 areshown and described as coupled to a single gas source, it will beunderstood by those of skill in the art that each of the inlet 406 andthe gas inlet 456 may be coupled to separate gas sources, each of whichsupply gas to the inlet 406 and the gas inlet 456 when delivery offluidized powder mixture to the target site is actuated and/ortriggered.

As shown in FIGS. 8 and 9, a device 500 may be substantially similar tothe device 400, unless otherwise indicated. The device 500 comprises acanister 502 defining a first interior space 504 within which powderedagent is received and fluidized to deliver a fluidized powder mixture toa target site of a patient for treatment. Rather than a separate fillerchamber, however, the canister 502 defines both the first interior space504 and a second interior space 550 which, when the device 500 is in anoperative position, extends above the first interior space 504. Inaddition, rather than filling the first interior space 504 with a fillermaterial to maintain a constant volume of material (powder and/orfiller) therein, the second interior space 550 houses additionalpowdered agent, which may be supplied to the first interior space 504via gravity as the fluidized powder mixture exits the first interiorspace 504 to be delivered to the target site. An inlet and outlet (notshown) are in communication with the first interior space 504 so thatonly the powdered agent contained within the first interior space 504 isfluidized to form the fluidized powder mixture and only the powderedagent within the first interior space 504 is permitted to exit thedevice 500 to the target site.

The second interior space 550 may be in communication with the firstinterior space 504 via an opening 554 extending therebetween. The device500 further comprises a door 558 movable between a first configurationprior to commencement of a treatment procedure, as shown in FIG. 8, anda second configuration during a course of treatment, as shown in FIG. 9.In the first configuration, the door 558 may extend over the entireopening 554 when fluidized powder mixture is not being delivered, toprevent the passage of any powdered agent from the second interior space550 to the first interior space 504. As shown via the dotted line inFIG. 8, the first interior space 504 contains a given volume of powderedagent therein.

When the user actuates and/or triggers delivery of the fluidized powdermixture, as shown in FIG. 9, movement of the door 558 may also betriggered so that the door 558 opens to expose the opening 554,permitting the passage of powdered agent from the second interior space550 to the first interior space 504. Actuation of the door 558 may betriggered in any of a number of different ways. For example, the door558 may include a motor that is activation, upon actuation of the device500, a magnetic mechanism that uses magnetism to open the door 558 uponactivation and/or pressure differentials created by the pressureincrease upon device actuation. The second interior space 550 mayinclude an angled surface 560 which directs the powdered agent towardthe opening 554 so that, when the door 558 is open, the powdered agentwithin the second interior space 550 is permitted to fall into the firstinterior space 504. Thus, the first interior space 504 is passively fedwith the additional powdered agent via gravity. As shown via the dottedline in FIG. 9, the volume of powder within the first interior space 504should remain constant during the course of treatment since the firstinterior space 504 is being fed via the second interior space 550 as thefluidized powder mixture is being delivered. The opening 554 may besized and/or otherwise configured to allow powdered agent to falltherethrough at a controlled rate selected to keep the volume ofpowdered agent within the first interior space 504 substantiallyconstant.

Although the additional powdered agent within the second interior space550 is described as being passively fed into the first interior space504 via gravity, in an alternate embodiment, as shown in FIGS. 10 and11, powdered agent within a second interior space 550′ of a canister502′ of a device 500′ may be actively fed into a first interior space504′ of the canister 502′ via, for example, a turbine 562′ which may bepowered via a gas flow. In this embodiment, a rotatable paddle 564′ ismounted within an opening 554′ extending between the first and secondinterior spaces 504′, 550′. The rotatable paddle 564′ is connected tothe turbine 562′, which is positioned along an exterior of the canister502′ and housed within a gas flow path 566′. The gas flow path 566′ maybe configured as a connecting element 524′ connecting a gas source to aninlet (not shown), which permits passage of gas therethrough into thefirst interior space 504. Thus, the connecting element 524′, in thisembodiment, extends along an exterior side of the canister 502′ toaccommodate the turbine 562′.

In a first configuration of device 500′, as shown in FIG. 10, in whichdelivery of fluidized powder mixture is not actuated and thus no gasflows through the flow path 566′, the turbine 562′ does not rotate andthus no powdered agent is permitted to pass from the second interiorspace 550′ to the first interior space 504′. As shown in FIG. 11, whendelivery of the fluidized powder mixture is actuated, in a secondconfiguration, the turbine 562′ is rotated via a flow of gas passingthrough the gas flow path 566′. Rotation of the turbine 562′correspondingly rotates the paddle 564′ to actively drive the powderedagent within the second interior space 550′ through the opening 554′ andinto the first interior space 504′. Since the flow of gas is initiatedwhen a user actuates and/or otherwise triggers delivery of a fluidizedpowder mixture to a target site, a supply of powdered agent from thesecond interior space 550′ to the first interior space 504′ will occursimultaneously with the exiting of powdered agent (e.g., the fluidizedpowder mixture) from the first interior space 504′ to maintain asubstantially constant volume of powdered agent within the firstinterior space 504′. Maintaining the volume of powdered agent within thefirst interior space 504′ will correspondingly maintain a substantiallyconstant delivery rate of the fluidized powder mixture.

Although the above embodiment describes a single gas source/supply, itwill be understood by those of skill in the art that the turbine 562′may be driven via a gas source separate from a gas source connected toan inlet of the device 500′ so long as a volume of powdered agentsupplied from the second interior space 550′ to the first interior space504′ corresponds to a volume of powdered agent exiting the firstinterior space 504′. In addition, although the embodiment describesactive transfer of the powdered agent via a gas powered turbine, activetransfer from the second interior space 550′ to the first interior space504′ may also occur via other mechanisms.

As shown in FIG. 12, a device 1200 for fluidizing and delivering apowdered agent (e.g., hemostatic agent) according to an embodiment ofthe present disclosure comprises a canister 1202 and a piston 1204movably coupled to the canister 1202. The canister 1202 is configured toreceive the powdered agent within an interior space 1206 thereof. Thecanister 1202 is subsequently filled with a gas via an inlet 1208 thatmay be connected to a gas source via, for example, a tubular member1212. The powder is fluidized via the gas to form a two-phase mixturethat may be sprayed onto the target site (e.g., bleeding site) via acatheter 1214 connected to an outlet 1210. The catheter 1214 is sizedand shaped and sufficiently flexible to be endoscopically inserted intoa patient body to the target site (e.g., along a tortuous path traversedby a flexible endoscope through a body lumen accessed via a natural bodyorifice). In order to maintain a substantially constant delivery rate ofthe mixture to the target site, the piston 1204 is movable relative tothe canister 1202 to decrease a volume of the interior space 1206,during the course of treatment of the target site. Thus, as a volume ofpowder within the canister 1202 is decreased, the volume of the interiorspace 1206 is also decreased to maintain a substantially constant powdervolume to canister volume ratio. The piston 1204 may be moved relativeto the canister 1202 in any of a number of different ways. In thisembodiment, the piston 1204 is moved via a pneumatic cylinder or motor1220.

The canister 1202 of this embodiment is formed of a rigid material todefine the interior space 1206, which is configured to receive thepowdered agent along with the gas to form the gaseous fluid mixture thatis sprayed on the target site to provide treatment thereto. The canister1202 extends longitudinally from an open first end 1216 to a closedsecond end 1218. The piston 1204 is movably coupled to the canister 1202at the first end 1216 and is movable toward the second end 1218 toreduce the volume of the interior space 1206. The piston 1204 enclosesthe interior space 1206 so that the powder, gas and/or the gas mixturedo not leak from the canister 1202, and exit the canister 1202 via theoutlet 1210 and from there into the catheter 1214 to exit toward thetarget site. Thus, the piston 1204 of this embodiment is received withinthe open first end 1216 and is substantially sized and shaped tocorrespond to a size and shape of an opening at the first end 1216. Inone example, the canister 1202 is substantially cylindrical while thepiston 1204 is substantially disc-shaped to be received within the openfirst end 1216 of the canister 1202. The canister 1202 is sized andshaped so that the piston 1204 is movable along at least a portion of alength thereof toward the second end 1218 to reduce a volume of theinterior space 1206 while also preventing leakage of anyfluids/substances received within the interior space 1206. In oneexample, the piston 1204 includes a sealing ring extending about acircumference thereof to prevent leakage of any powder, gas and/or fluidtherepast.

As described above, the device 1200 also includes the inlet 1208 viawhich gas is introduced into the interior space 1206 and the outlet 1210via which the fluidized powder is delivered to the catheter 1214 toreach the target site. In one embodiment, each of the inlet 1208 and theoutlet 1210 are configured as an opening extending through a portion ofthe piston 1204 to be connected to the tubular member 1212 and thecatheter 1214, respectively. It will be understood by those of skill inthe art, however, that the inlet 1208 and the outlet 1210 may bepositioned on or along any portion of the canister 1202 and/or thepiston 1204 so long as the inlet 1208 is configured to receive a highpressure gas therethrough and into the interior space 1206, and theoutlet 1210 is connectable to a delivery element such as, for example,the catheter 1214, which delivers the fluidized mixture from theinterior space 1206 to the target site. It will also be understood bythose of skill in the art, that although the inlet 1208 is described asconnected to the gas source via the tubular member 1212, the inlet 1208may be connected to the gas source via any of a number of couplings solong as sufficient gas flow is deliverable therethrough. In addition,although the outlet 1210 is shown and described as an opening extendingthrough the piston 1204, it will be understood by those of skill in theart that the outlet 1210 may also be configured to include a hypotubeextending into the interior space 1206 so that fluidized mixture formedwithin the interior space 1206 may be received within the hypotube to bedelivered to the target site via the catheter 1214.

In this embodiment, the piston 1204 is movable relative to the canister1202 via a pneumatic cylinder or motor 1220. The device 1200 may beprogrammed to include one or more inputs such as, for example, time.When it is desired to deliver the fluidized mixture to the target site,the user may initiate delivery using a controller such as a trigger. Forexample, when the user depresses the trigger to deliver the fluidizedmixture, the piston 1204 moves toward the second end 1218 at a presetrate. When the user releases the trigger, the piston 1204 may stop,maintaining its position relative to the canister 1202 until the userdepresses the trigger again. Alternatively or in addition, the device1200 may use other inputs such as, for example, inputs based on flowand/or pressure sensors within the interior space 1206 of the canister1202, the inlet 1208 and/or the outlet 1210.

Although the piston 1204 of the device 1200 is described and shown asdriven via the pneumatic cylinder or motor 1220, it will be understoodby those of skill in the art that the piston 1204 may be moved from itsinitial position proximate the first end 1216 toward the second end 1218via any of a variety of different drive mechanisms, examples of whichwill be described in further detail below. In addition, although thepiston 1204 is shown as forming a base (e.g., bottom portion) of thecanister 1202, it will be understood by those of skill in the art thatthe piston 1204 may be coupled to the canister 1202 in any of a numberof configurations. In particular, the piston 1204 may also be configuredas a lid (e.g., top portion) of the canister 1202. In a furtherembodiment, the device 1200 may include more than one piston 1204, eachof which are movable relative to the canister 1202 to reduce the volumeof the interior space 1206 thereof.

According to example method using the device 1200, the canister 1202 maybe filled with the powdered agent such as, for example, a hemostaticagent, prior to assembly of the device 1200. Upon filling the canister1202 with a desired amount of powder, the canister 1202 and the piston1204 are assembled, the inlet 1208 is coupled to the gas source via, forexample, the tubular member 1212, and the outlet 1210 is coupled to thecatheter 1214. The catheter 1214 may then be inserted to the target sitewithin the body through a working channel of a delivery device such asan endoscope. The user may depress a trigger or other controller tointroduce a high flow gas into the interior space 1206 of the canister1202 to form the fluidized mixture and deliver the fluidized mixture tothe target site (e.g., a bleeding site) to provide treatment thereto.When the trigger is depressed, the pneumatic cylinder or motor 1220 isoperated to move the piston 1204 toward the second end 1218 reducing thevolume of the interior space 1206 by an amount corresponding to thereduction in the volume of powder remaining within the interior space1206 as reduced the powder exits the canister 1202 via the outlet 1210.When the user releases the trigger, both the delivery of the fluidizedmixture and the movement of the piston 1204 are halted. Thus, the piston1204 moves only while the fluidized mixture is being delivered so thereduction in the volume of the interior space 1206 corresponds to thereduction in the volume of powder remaining housed within the interiorspace 1206. As described above, a rate of movement of the piston 1204may be based on inputs such as, for example, time, flow and/or pressurewithin the canister 1202, inlet 1208 and outlet 1210. In one embodiment,the piston 1204 is configured to move at a rate which maintains asubstantially constant ratio of the volume of the interior space 1206available in the canister 1202 to the volume of remaining powder tomaintain a substantially constant fluidized mixture delivery rate.

As shown in FIG. 13, a device 1300 according to another embodiment issubstantially similar to the device 1200, comprising a canister 1302 anda piston 1304 movably coupled thereto to move from an initial positionproximate a first end 1316 of the canister 1302 toward a second end 1318to reduce a volume of an interior space 1306 of the canister 1302 as afluidized powder mixture is delivered to a target site. Similarly to thedevice 1200, high flow gas is delivered to the interior space 1306 tofluidize a powdered agent received within the canister 1302 to form afluidized mixture for delivery to a target site in the body. Gas isreceived within the canister 1302 via an inlet 1308 connected to a gassource via, for example, a tubular member 1312. The fluidized mixture isdelivered to the target site via a delivery catheter 1314 connected toan outlet 1310 of the device 1300. In this embodiment, however, thepiston 1304 is moved via a chamber 1320 including an expandable member1322, which expands as gas is received therein. In particular, when auser triggers a controller (e.g., depresses a trigger) to deliver thefluidized mixture to the target site, a portion of the gas is divertedinto the expandable member 1322 so that the gas expands the expandablemember 1322, as shown in broken lines in FIG. 13, thereby moving thepiston 1304 toward the second end 1318.

The chamber 1320, which houses the expandable member 1322, in thisembodiment is connected to the first end 1316 of the canister 1302 on aside of the piston 1304 opposite the interior space 1306 so that, as theexpandable member 1322 expands, the piston 1304 is moved toward thesecond end 1318 of the canister 1302. The expandable member 1322 is alsoconnected to the gas source via a connecting member 1324, which includesa one way valve so that gas may pass therethrough in a first directioninto the expandable chamber 1322, but is prevented from flowing in asecond direction out of the expandable chamber 1322. As described above,gas is directed into the chamber 1320 only while the fluidized mixtureis being delivered to the target site so that a reduction of the volumeof the interior space 1306 corresponds to a reduction in volume of thepowdered agent within the canister 1302. Similarly to the device 1200,the device 1300 may receive inputs corresponding to flow, pressureand/or time, that may control a rate at which the piston 1304 is movedtoward the second end 1318. It will be understood by those of skill inthe art that the device 1300 may be used in a manner substantiallysimilar to the device 1200.

As shown in FIGS. 14 and 15, a device 1400 according to anotherembodiment may be substantially similar to the devices 1200 and 1300described above, comprising a canister 1402 for receiving a powderedagent within an interior space 1406 thereof and a piston 1404 movablycoupled to the canister 1402. High flow gas is delivered to the interiorspace 1406 via an inlet 1408 that is connected to a gas source to form afluidized powder mixture for delivery to a target treatment area via adelivery catheter 1414 connected to an outlet 1410 of the device 1400.The piston 1404 is movable from an initial position proximate a firstend 1416 of the canister 1402 toward a second end 1418 to reduce avolume of the interior space 1406 as a volume of the powdered agentwithin the interior space 1406 is reduced. The device 1400, however,further includes a turbine 1426 connected to a threaded rod 1428 towhich the piston 1404 is threadedly coupled. The turbine 1426 is housedwithin a bypass 1424 connected to the first end 1416 if the canister1402. A portion of the gas is diverted through the bypass 1424 when theuser triggers a controller to deliver the fluidized mixture. The flow ofgas through the bypass 1424 spins the turbine 1426, thereby causing thethreaded rod 1428 to rotate about a longitudinal axis thereof. As thethreaded rod 1428 is rotated, the piston 1404 is moved longitudinallytherealong toward the second end 1418.

As shown in FIG. 15, the bypass 1424 including a first opening 1430through which gas is received and second opening 1432 through which gasexits so that gas flows through the bypass 1424 from the first opening1430 to the second opening 1432 to rotate the turbine 1426 housedtherein. The threaded rod 1428 is connected to the turbine 1426 so thatrotation of the turbine 1426 results in rotation of the threaded rod1428. Since the piston 1404 is threaded over the rod 1428, rotation ofthe threaded rod 1428 causes the piston 1404 to be moved longitudinallytherealong. The piston 1404 is threaded over rod 1428 so that rotationof the threaded rod 1428 via the flow of gas through the bypass 1424results in the longitudinal movement of the piston 1404 toward thesecond end 1418. Similarly to the device 1300, a portion of the gas isonly diverted through the bypass 1424 during delivery of the fluidizedmixture so that a reduction in volume of the interior space correspondsto a volume of powder remaining in the interior space 1406. It will beunderstood by those of skill in the art that the device 1400 may be usedin a manner substantially similar to the devices 1200, 1300, asdescribed above.

As shown in FIG. 16, a device 1600 according to another embodiment ofthe present disclosure may be substantially similar to the devices 1200,1300, and 1400, described above, comprising a canister 1602 configuredto receive a powdered agent therein for fluidization via a gas. Similarto the devices 1200, 1300, and 1400, a volume of an interior space 1606of the canister 1602 is reduced as a fluidized mixture is delivered to atarget site for treatment. Rather than reducing the volume of theinterior space 1606 via a movable piston, however, the device 1600includes an expandable member 1604 which expands into the interior space1606, as shown in broken lines in FIG. 16, of the canister 1602 toreduce the volume thereof.

Similarly to the devices 1200, 1300, and 1400, gas is supplied into thecanister 1602 via an inlet 1608, which may be connected to a gas sourcevia a connecting member 1612. The fluidized mixture is delivered to thetarget site via a delivery catheter 1614 connected to an outlet 1610.The device 1600 further comprises a secondary chamber 1620 connected tothe canister 1602. Similarly to the device 1300 described above, aportion of the gas from the gas source may be diverted into thesecondary chamber 1620 during delivery of the fluidized mixture. Aninterior space 1634 of the secondary chamber 1620 is separated from theinterior space 1606 of the canister 1602 via the expandable member 1604.In this embodiment, the expandable member 1604 is configured as anexpandable diaphragm extending between the canister 1602 and thesecondary chamber 1620 so that, when gas is received within the interiorspace 1634 of the secondary chamber 1620 via feed tube 1624, a pressuredifferential between the interior space 1634 of the secondary chamber1620 and the interior space 1606 of the canister 1602 causes theexpandable member to deflect into the canister 1602, as shown in brokenlines in FIG. 16 reducing the volume of the interior space 1606.

As described above with respect to the devices 1300, 1400, gas is onlydiverted into the secondary chamber 1620 during the delivery of thefluidized mixture. When delivery is triggered gas is diverted to thesecondary chamber 1620. When the user releases the trigger for delivery,delivery of gas to the secondary chamber 1620 is halted. As alsodiscussed above, the amount of flow diverted to the secondary chamber1620 may be dictated by time, pressure and/or flow detected within thedevice 1600. As more gas flows into the secondary chamber 1620, itspressure increases to force the diaphragm to deflect further into theinterior space 1606 of the canister 1602. Thus, the device 1600 may beutilized in a manner substantially similar to the devices describedabove.

Although the device 1600 shows and is described with respect to a singleexpandable diaphragm, it will be understood by those of skill in the artthat the device 1600 may include more than one expandable diaphragm andthe expandable member may have any of a variety of shapes andconfigurations.

As shown in FIG. 17, a device 1700 according to another embodiment maybe substantially similar to the device 1600, described above, comprisinga canister 1702 including an expandable member 1704 which expands toreduce a volume of a first interior space 1706 of the canister 1702 as apowdered agent received therewithin is fluidized and delivered to atarget site for treatment. In this embodiment, however, the expandablemember 1704 may be housed within the canister 1702 to define both thefirst interior space 1706 in which the powdered agent is fluidized and asecond interior space 1720 into which a portion of a gas may be divertedto cause the expandable member 1704 to deflect into the first interiorspace 1706 to reduce a volume thereof. A first end 1716 of the canister1702 may be substantially closed via a base portion 1740. An inlet 1708for supplying gas into the first interior space 1706 and an outlet 1710via which the fluidized mixture is delivered to the target site mayextend through the base portion 1740 in communication with the firstinterior space 1706.

The expandable member 1704 may, in one example, have a substantiallycylindrical configuration. The cylindrically shaped expandable member1704 is housed within the canister 1702 so that an interior of theexpandable member 1704 defines the first interior space 1706 withinwhich the powdered agent is housed and subsequently fluidized via a highflow gas supplied from a gas source thereto via the inlet 1708. Thesecond interior space 1720 is defined via an exterior surface 1736 ofthe expandable member 1704 and an interior surface 1738 of the canister1702 so as the fluidized mixture is delivered to the target site fromthe first interior space 1706 via a delivery catheter 1714 connected tothe outlet 1710, a portion of gas from the gas source gas is divertedinto the second interior space 1720 via a connecting element 1724. Apressure differential between the first and second interior spaces 1706,1720 causes the expandable member 1704 to deflect into the firstinterior space 1706, as shown in broken lines in FIG. 17, toward anexpanded configuration, as shown via the broken lines in FIG. 17,reducing the volume of the first interior space 1706 as a volume of thepowder in the first interior space 1706 is reduced. In one embodiment,in the expanded configuration, the expandable member 1704 may form asubstantially hourglass shape. It will be understood by those of skillin the art, however, that the expandable member 1704 may have any of avariety of shapes and configurations so long as the expandable member1704, when expanded, reduces a volume of the first interior space 1706.Similarly to the devices described above, gas is only diverted into thesecond interior space 1720 during delivery of the fluidized mixture andmay be controlled via inputs including time, and/or flow and/or pressurewithin the device 1700.

Although the device 1700 is shown and described as including asubstantially cylindrically shaped expandable member 1704, it will beunderstood by those of skill in the art that the expandable member 1704may have any of a variety of shapes so long as the expandable memberdefines first and second interior spaces 1706, 1720, as described above.

As shown in FIG. 18, a device 1800 according to another embodiment maybe substantially similar to the device 1700 described above, comprisinga canister 1802 and an expandable member 1804 defining a first interiorspace 1806, in which a powdered agent is fluidized via gas from a gassource to form a fluidized mixture, and a second interior space 1820,which receives a portion of gas diverted from the gas source duringdelivery of the fluidized mixture to a target treatment area. The firstinterior space 1806 is defined via an interior wall 1805 of theexpandable member 1804. The second exterior space 1820 is defined via anexterior wall 1836 of the expandable member 1806 and the interiorsurface 1838 of the canister 1802. In this embodiment, however, theexpandable member 1804 extends from a first end 1816 of the canister1802 to a second end 1818 of the canister 1802 so that, in an initialbiased configuration, the expandable member 1804 may substantiallycorrespond in shape to the canister 1802. As the second interior space1820 is filled with diverted gas, however, the expandable member 1804deflects into the first interior space 1806, as shown in broken lines inFIG. 18, increasing a volume of the second interior space 1820 andthereby reducing a volume of the second interior space 1820.

Similarly to the device 1700, the device 1800 also includes a baseportion 1840 at a first end 1816 of the canister 1802 for enclosing thefirst and second interior spaces 1806, 1820. An inlet 1808 and an outlet1810 extend through the base portion 1840 in communication with thefirst interior space 1806 so that gas may be supplied thereto via theinlet 1808 to fluidize the powdered agent therein and so that thefluidized mixture may be delivered to the target site via the outlet1810. A portion of the gas from the gas source may be diverted into thesecond interior space 1820 via a connecting element 1824, which may bepositioned along the base portion 1840 in communication with the secondinterior space 1820.

As described above, during delivery of the fluidized mixture to thetarget site, a portion of the gas is diverted into the second interiorspace 1820 so that a pressure differential between the first and secondinterior spaces 1806, 1820 causes the expandable member to be divertedradially inward, as shown in broken-lines in FIG. 18, to reduce thevolume of the first interior space 1806. Thus, as the volume of thepowdered agent within the first interior space 1806 is reduced, thevolume of the first interior space 1806 is correspondingly reduced tomaintain a substantially constant delivery rate of the fluidizedmixture. In a diverted configuration, the expandable member 1804 maytake on a substantially conical shape. It will be understood by those ofskill in the art, however, that the expandable member 1804 may have anyof a configurations, shapes and sizes so long as the expandable member1804 is formed of a flexible, deflectable material which defines both afirst interior space 1806 within walls thereof, and a second interiorspace 1820 between the expandable member 1804 and walls of the canister1802.

As shown in FIG. 19, a device 1900 according to another embodiment maybe substantially similar to the devices 1600, 1700, and 1800 describedabove, comprising a canister 1902 and an expandable member 1904, whichexpands to reduce a volume of an interior space 1906 of the canister1902 as a powdered agent is fluidized and delivered to a target site oftreatment. The volume of the interior space 1906 is reduced tocorrespond to a reduction in a volume of the powdered agent within theinterior space 1906. The expandable member 1904 in this embodiment,however, is configured as an expandable balloon housed within theinterior space 1906. Thus, as a volume of the balloon 1904 is increasedas it is inflated, the volume of the interior space 1906 is decreased.

Similarly to the devices 1600, 1700, and 1800, the device 1900 includesan inlet 1908 for supplying a gas to the interior space 1906 to fluidizethe powdered agent and an outlet 1910 via the fluidized mixture isdelivered to the target site. The inlet and outlet 1908, 1910,respectively, may extend through a base portion 1940 of the device 1900which is coupled to an end of the canister 1902 to define the interiorspace 1906. A portion of the gas supplied to the device 1900 may bediverted to the expandable member 1904 via a connecting element 1924 tocause the balloon to become inflated, filling the interior space 1906.As described above, the inlet 1908 may have any of a variety ofconfigurations and, in one embodiment, may include a hypotube 1911extending into the interior space 1906. The hypotube 1911 may include aslot 1944 extending through a wall thereof along a portion thereof. Theinflated expandable member 1904 may fill the space, surrounding thehypotube 1911 without restricting gas and powder flow through the slot1944. Although the hypotube 1911 is described as including the slot1944, it will be understood by those of skill in the art that the term“slot” may refer to any opening or hole extending through a wallthereof.

The connecting element 1924 may be coupled to the base portion 1940, asshown, to deliver gas to the expandable member 1904. It will beunderstood by those of skill in the embodiment, that the connectingelement 1920 may extend through the interior space 1906 to connect tothe expandable member 1904. Alternatively, as shown in FIG. 20, a device1900′ may have a separate feed line 1924′ which extends through aportion of a canister 1902′ to supply gas to an expandable member 1904′housed therein. It will be understood by those of skill in the art thatan expandable member 1904, 1904′ having a balloon configuration may besupplied with gas for inflating the expandable member via any of avariety of mechanisms.

Although the above embodiments are described as diverting a portion ofgas from a gas source/supply to drive movement of a piston or expansionof an expandable member, it will be understood by those of skill in theart that the devices described above may include one or more gassource(s) for providing gas to both the interior space and for drivingthe piston and/or causing expansion of the expandable member.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the disclosed device withoutdeparting from the scope of the disclosure. For example, various otherstructures and techniques for maintaining a consistent output ofmaterial from a dispensing device to a target site may be achieved.Other embodiments of the disclosure will be apparent to those skilled inthe art from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples be considered as exemplary only, with a true scope and spiritof the invention being indicated by the following claims.

What is claimed is:
 1. A device for fluidizing and delivering a powderedagent, comprising: a canister extending longitudinally from a first endto a second end and defining an interior space within which a powderedagent is received; an inlet coupleable to a gas source for supplying gasto the interior space to fluidize the powdered agent receivedtherewithin to create a fluidized mixture; an outlet via which the gasmixture is delivered to a target area for treatment; a tube extendingfrom a first end in communication with the outlet to a second open endextending into the interior space, the tube including a slot extendingthrough a wall thereof so that gas mixture is passable from the interiorspace through the outlet via the second end and the slot; and a doormovably coupled to the tube so that the door is movable over the slot tocontrol a size of the slot open to the interior space of the canister.2. The device of claim 1, wherein the door is configured as an overtubemovably mounted over the tube.
 3. The device of claim 1, furthercomprising a stabilizing ring extending radially outward from theovertube to an interior surface of the canister to fix the tube relativeto the canister.
 4. The device of claim 1, wherein the canister isrotatable relative to the tube to move the overtube longitudinallyrelative to the tube and control the size of the slot open to theinterior space.
 5. The device of claim 1, further comprising a lidcoupleable to the canister to enclose the interior space, the inlet andthe outlet configured as openings extending through the lid.
 6. Thedevice of claim 1, further comprising a delivery catheter coupleable tothe outlet, the delivery catheter sized and shaped to be insertedthrough a working channel of an endoscope to the target area.
 7. Adevice for fluidizing and delivering a powdered agent, comprising: acanister extending longitudinally from a first end to a second end andincluding a first interior space within which a powdered agent isreceived; a first inlet coupleable to a gas source for supplying gas tothe interior space to fluidize the powdered agent received therewithinto create a fluidized mixture; an outlet via which the gas mixture isdelivered to a target area for treatment from the first interior space;and a filler chamber in communication with the first interior space viaa filler inlet, the filler chamber containing a filler material passablefrom the filler chamber to the first interior space to maintain asubstantially constant volume of material therein, wherein the materialincludes at least one of the powdered agent and the filler material. 8.The device of claim 7, wherein the filler material includes one of mockparticles, beads, bounce balls, and a foam material.
 9. The device ofclaim 7, wherein the filler material is sized and shaped so that thefiller material cannot be passed through the outlet.
 10. The device ofclaim 7, wherein the filler chamber is supplied with a gas to drive thefiller material from the filler chamber into the first interior space.11. The device of claim 7, wherein the filler chamber is configured as asecond interior space defined via the canister.
 12. The device of claim11, wherein the second interior space includes an angled surfacedirecting the filler material to the filler inlet.
 13. The device ofclaim 7, wherein the filler material is additional powdered agent. 14.The device of claim 7, further comprising a door movable relative to thefiller inlet between a first configuration, in which the door covers thefiller inlet, to a second position, in which the door opens the fillerinlet to permit filler material to pass therethrough from the fillerchamber to the first interior space via gravity.
 15. The device of claim7, further comprising a turbine connected to a paddle housed within thefiller inlet, the turbine driven by a flow of gas so that, when a flowof gas is received within a flow path housing the turbine, the turbinerotates to correspondingly rotate the paddle so that filler materialwithin the filler chamber is actively driven therefrom and into thefirst interior space.
 16. A method, comprising: supplying a gas to aninterior space within a canister within which a powdered agent isreceived to fluidize the powdered agent, forming a fluidized mixture;and delivering the fluidized mixture to a target area within a patientbody via a delivery catheter inserted through a working channel of anendoscope to the target area, wherein during delivery of the fluidizedmixture, a door movably mounted over the tube is moved relative to aslot extending through a wall of a tube extending into the interiorspace of the canister in communication with the delivery catheter, tocontrol a size or an area of the slot exposed to the interior space. 17.The method of claim 16, wherein the door is an overtube movably mountedover the tube.
 18. The method of claim 17, wherein the overtube is movedrelative to the slot by rotating the canister relative to the tube, theovertube fixed relative to the canister via a stabilizing ring extendingradially outward from the overtube to an interior surface of thecanister.
 19. The method of claim 18, wherein rotation of the canistermoves the overtube longitudinally relative to the tube.
 20. The methodof claim 16, wherein the door is moved relative to the slot via one ormore of mechanically, by physically twisting, or pneumatically with theflow of gas.